A driving apparatus for a railway vehicle is configured to include electric motors set in a truck frame, axles rotatably set in the truck frame and having wheels disposed at both ends, and transmission gears each of which is coupled to the electric motor and the axle and configured to reduce the rotating speed of the electric motor and transmit a driving force to the axle. The torque of the electric motor is transmitted to the transmission gear via a gear coupling and decelerated to a predetermined value by the transmission gear.
A gear coupling in the past represented by Patent Literature 1 described below is configured to concentrically fasten, with a plurality of bolts, two outer cylinders, in which internal tooth gears meshing with external tooth gears respectively provided at a shaft end of a driving shaft of an electric motor and a shaft end of a small gear shaft (a driven shaft) of a transmission gear are formed, thereby being capable of securing reliable transmission of power even when a deflection occurs between the driving shaft and the driven shaft.